Marine propulsion.



Y. WA DAGAKI. MARINE PROPULSION. APPLIOATIOfi FILED JAN. 20, 1908.

Patented Sept. 22, 1908.

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q vihtcaam Y ASUZO WADAGA .KI,

OF SASEBO, JAPAN.

MARINE PROPULSION.

Specification of Letters Patent.

Patented Sept. 22, 1008.

Application filed January 20, 1908. Serial No. 411,668.

To all whom it may concern:

Be it known that I, Y ASUZH WAnAoAKi, e subject of the Emperor of Joplin, residing at Snseho, in the Province of llizon, Nugnsnki Ken, Japan, have invented certain new and useful Improvements in Marine Propulsion; and I do declare the following to he a full, clear, and exact description of the invention, such as will enable others skilled in. the art to which it nppertuins to ,lllitkO end use the same.

This invention relntes to improvements in marine 'n'opulsion.

The o hject of the invention is to improve the construction of the propeller casing shown in United States Letters-letent, No. 856,115, granted. to lllQ June 4, 1907, and to coml'iine said casing with. the rudder of ,&

vessel.

Another object of the invention to make the she e of the inlet end of the water channel wit i'in the propeller casing such that it will offer the least possible nn'iountof resistanee to the inflow of WlLl O-l.

Another object oi" the inven tion is to locate the point oi nuxinium eoi'itruttion of the water ehem'iel wherein the screw n-o'peller operates lILS n car to the inlet end of the casing as possible, and to make its discharge pnssage as long as possible wi th a. view of obtaining a better utilization of the residual energy still contained in the mass of outflowing water. I

Another object of the invention is to make. the angle of convergence of the discharge passage in the casing as small as possible and to gradually increase-from a point o-fnmximum. contraction toward the after-end so as to allow the stream. of out-going water to keep itself in chiset uch with the inside wall of the casing for as long a time as possible, and to thus avoid an unnecessary waste of power in. the erection. of eddies arising from the sudden. .onlurgiunont oi the sortionul urea. of the strewn.

Another object is to roduro the loss of use- .ul thrust.- which only he oci'usiomul by an excessive inclination of the propeller shell.

- from its usu:il'l'in'esindrnft longitiulinul d ircrtion.

A further object ol the invention is to avoid the loss of useful thrust which may he caused by the intorferenceol the rudder post on the notion. oi the pro 'ie-ller (nee when the rudder is fitted in proximity to the screw propeller, an d in the some vertical. plane with. the .nopeller shaft.

Vl ith. these objects in view, the invention consists of certain novel features of construction, combination and arrangement of parts as will he described hereinafter and articulerly pointed out in the e pended e aims.

In the accompanying (rawings, Figure 1 is a side elevation of the stem end of a vessel showing the application of the invention thereto; Fig. 2 18 an enlarged sectional view of the propeller casing showing the position of the some on c rudder, and the position of the propeller within the casing; *ig. 3 is a horizontal sectional View through the rudder showing the casing in top plan view; Fig. 4 is a vertical sectional view through the rudder and the casing; Fig. 5 is a. similar view showing a modified construction of the casing; Fig. 6 is a. side elevation of a portion of e vessel showing the arrangement of the casing and the position of the propeller when the some is connected. with and operated by a. turbine of large diameter; and Fig. 7 is a vertical sectional view of a propeller casing embodying my improved construction, but formed and, supported independently from the rudder.

Referring more particularly to the drawings, 1 denotes a rudder, the upper portion of which may be of the usual or any desired construction and is here shown as being formed integral with the lower end of the rudder post, 2. of the rudder and forming a port of the some, is n tuhulnrcasing, .3, the outer surface of which is preferably oylii'ulrical in form, shown although in. some eases it only be made slightly conical tapering aft. The casing, 3, is u'ei'i-irnhly formed in two sections, and led ivided either longiludinnll on u central horizontal plane, as shown in Fig.

4 of ihe drawin s or in u vertical lon itudi h Y b nnl plume, us shown in Fig. 5 ol the drawings,

lho sect-ions oi' the cosin helm suil-uhlv".

hol-liod logelhel', us shown. The inner wall of the casing llnres outwardly toward. its forward end to form an enlarged. inlet opi "l- Seeured to the lower edge ing 1 or the passage of the water entering the some. From the point of the maximum contraction of the inner well of the casing toward the rear or discharge end of (he some, said inner wnll diverges gradually, thus prolower sections, 5

. fastening bolts, 8, by

vertical plane in line with 10, are providiid -which the annular c Viding for the utilization of the residual energy still contained in the mass of outfiowin water after being acted u on by the propel er blades. the casing offers the least possible amount of resistance to the inflow of the water and provides for the admission of a large quan: tity of the latter which is sucked in from all forward directions by the flaring or hellshape'd mouth of the casing.

' In the form of casing shown in Figs. 1 to 4, the inner wall, 4, is shown as bein an upper section, 5, which is formed in-teg'ia with or suitably secured to the lower edge of the rudder, and a lower section, 6. The inner or meeting edges of the upper and forming pro'ecting flan es, 7, which are provided with alined bo t holes adapted to receive means of which said sections are secured together.

In Fig. 5 of the drawings, the casing is shown as being divided lon itudinally on a the center of the casing to form right and left-hand sections, 9, the ner or meeting edges of which are rovidda with laterally pro'ecting upper and ower flanges, 1'0 and 12, he upper flanges, with bolt holes which are ada ted to al o with similar holes formed in t e lower edge of the rudder to which said .upper flanges are adapted to be bolted, thus securely fastening the casing to the rudder. The lower flanges 12 are also provided with bolt holes through which are inserted fas-' tening bolts by,means of which thelower edges of the sections of the casing are secured to ether.

- i bot forms of thecasing, the fastening flanges are provided with-longitudinally disposed recesses, 13, inwhich are adapted to be secured the edges of substantially semi-cylindrical coveringlates, 14, by means of annel around the casing formedby the inwardly curved wall, 4, is

covered, and by means offlwhich the outer surface ofthe casing resents a smooth 0 linhe outer ends 0 the mdrical plates, 14, are engaged with annular recesses, i5, formed in the outer surfaces of the sections of the inner ,wall 4, of the casing, as shown.

In Fig. 6 of the drawings, shown as applied to a vessel drical a 'pearance. semi-cy the casing is in the engine room of which is fitted a 'turbine'of large diameter, which makes it necessary to, set the propeller shafting at'an excessive inclination'from the direction :of the vessel's progress. When the casing is. used in; coneller arranged in. this 1 manner, thec'enterlme of the c'asingmay be set ata different nection with a prop angle to the inclinationxof The flaring in et end of and 6, of the casing, are provided with integrally formed laterally 4 for useful purpose the water in the-tail-race of lengthene formed with a the propeller sha fting, and info, direction more nearly parallel to a horizontal plane or 16, in whichis formed an outer bearing, 17,

d ,for the propellershaft.

In Fig. 7 1s showna sectional'view of a casingconstructed in accordance with'the invention, adapted to be supported on. a vessel .independently of the-rudder." shown in this figure,

the inner wall, 18, has the same curvature as described 'in connec- .tion with the casing shown inthe former figures.

The inner wall, 18, as shown in Fig. 7 is divided transversely to form front and rear sections, the inner edges of which are; rovided with flanges, 19, adapted to be h ted. to ether, as shown. The inner wall is. ro-

In the casing but formed separately from and l vi ed with an outer cylindrical cover p, ate, 20, and in the forward section of the inner wall is formed a bearing, of the ropeller, 23, which is "mounted in the casing at the point of the greatest contraction of the inner wall.-

In the operation of In improved c the water is sucked readi y into the inlettend of the same fromall forward directions inI-the shape of an inverted -cone, so that, a "large uantity'of water is permitted toenter with t e. least possible resistance. It will be 21, fortl 1 e shaft,'22,

.noted that the length re uired forlthe inlet passage of water at the orward end of the propeller casing is much shorter in "the present case, than that shown and described in my patent hereinbefore mentioned. In passing through the most contracted art of the casing, the water findsitself Erought to agradually expanding part ofthe its velocity correspondingly reduced in nearly the same manner-as. nmy previous tent, but in the form shown herein, a much "Qtter opportunity-is plresented to recover discharge Y been shortene In my previous system of marine s on as descnbed in my former,

oper'atively i channel in the after-body of the casing,'iwith a netic energ of the v thepropell'er, as th assage of the casing is as much in proportion'as the inlet end propuLi:

atent, the

discharge passage of the waters annel was present system thisis done with a single easy curve.

creased length of the diseharg' e assage that is-obtained in the manner. hereinbeforefds' scribegi. 'makes it possible toavoid thersud den 'e argement of sectional and the his iiact, combined with the 'in-i ouble curvature but in-the the large diameter of the turbine, as shown makes it necessary to set the center.

in Fig; 6, line of the impeller shaft at a considerable inclination irom the direction of the vessel's progrcss. With an ordinary screw propeller under such circumstances, the loss of useful thrust would evidently become ve serious. With my system of screw propel er, however, the center line of the propeller casing can always be fitted in any desired direction, quite irrespective to the direction of the screw shafting, so that a part of the energy lost by any excessive inclination ofthe propeller shaft will always be recovered by fixing the propeller casing in a suitable direction.

Havin thus fully described my invention, whatI c aim as new, and desire to secure by Letters-Patent, is:

1. A propeller casing formed in longitudinal sections, the inner walls of which are formed to irovide a short converging channel at the orward end of the casing, and a long graduliilly diverging channel in the rear portion of the casing wherein a screw pro-v peller is arranged to operate at the point of maximum contraction of said convergent and ,divergcnt water channel, substantially as described.

2. A ships rudder having formed on its lower edge a cylindrical casing, the inner wall of which is curved to form a short outwardly flaring passage at the inlet end of the casing, and a long gradually outwardly flaring or diverging rear portion opening at the rear or discharge end of the casing, substantially as described.

3. In combination with a ships rudder, a

nesses.

casing formed in longitudinal sections, one of which is arran ed on the lower edge of the rudder, lateral y projectin flanges formed 4 on the meeting edges of saii sections, fastening bolts adapted to secure said sections toether, an inwardly curved inner wall formed in said sections to provide a convergent and divergent water channel, and outersegmental coverin plates adapted to be arran ed around sai( inner wall to provide a cyi' indrical outersurface for said casing, substan- I tially as described.

4. In a system of marine propulsion, a pro- 5 'peller casing having an inner wall formed to provide a short outwardly flarin passage at the inlet end of the casin and a on'g gradually tapered outwardly aring or diverging passage at. the discharge end of'the' casing, a pro e ler operatively arranged in said 'casin at t e point of maximum contraction of sai passage, and means whereby said casing is supported at an angle to the direction of the propeller shaft, thereby providing for a ar- 5 tial recove of energy which would ot erwise be lost an excessive inclination of the propeller sha t. r

5. In a system of marine pro ulsion, a rudder, a pro eller casing adapte to form partof said ru der,. an inner curved wall arranged in said casing toform a assage having a short convergent forward em and a long gradually diverging rear passage, and a propeller op. eratively arranged in said casing at the point :5 of maximum contraction of. said' channel, substantially as described. a I In testimony whereof I have hereunto set my hand in presence of two subscribing wit- YASUZO .VVADAGAKI. 'Witnesses:

' CARLETON lVlILLEIt,

Tsunszo Surcro. 

